Carrie Underwood lifts weights for perfectly toned arms

Carrie Underwood's trainer Erin Oprea mixes up heavy and light weights to help the country star achieve her toned arms.

Carrie Underwood's not scared of using weights when it comes to working out.

The country star often shows off her toned arms on the red carpet, and also boasts washboard abs and enviable legs.

She trains with Nashville-based fitness expert Erin Oprea, who also counts fellow country star Kelsea Ballerini as a client.

"(Carrie's) not scared of weights," Erin told Women's Health magazine. "Weights make pretty muscles, and pretty muscles burn lots of calories. So the more muscle you have, the more calories you burn and it's like a double whammy.

Asked about how Carrie achieves her sculpted arms, Erin ran through some of their favourite exercises. Pullups, lateral raises, squat and press, plank rows and tricep dips all feature in the pair's fitness regime, and Erin says these moves are easy to replicate.

Carrie, 33, hasn't always been so into her fitness, and previously admitted the fat jibes she received after winning the fourth season of American Idol served as a wakeup call.

"Back when I was on American Idol, I was a bit heavier than I am now," she previously told Us Weekly. "That was the first time I was exposed to the public talking about me, so it was impossible not to look online and see what they were saying. Apparently I was fat. Of course I wasn't, but sometimes words people choose are not the nicest.

"I feel much better now at 33 than I did when I was 20 because I take better care of myself."